The examination of 2033 patients with severe mechanical injuries has shown that in most patients with traumas of the head, chest and upper extremities of the same localization (isolated or multiple) the volume of blood loss was not more than 20% of the circulating blood volume. Isolated and multiple injuries of the abdomen, pelvis, spine and lower extremities in 28-54% of the patients were followed by blood loss more than 20% of the circulating blood volume. Associated traumas in most cases were followed by massive blood loss (more than 40% of the CBV).